Air cleaner



Sept. 8, 1936. F. A. DONALDSON AIR CLEANER Filed April 13, 1955 /fwf/vmeFfa/1k A Dona/daan Patented Sep't. 8, 193e AmcnmimmL rmx a. nomma,manon, man. i Animation -Anru "13,1935, serai No. 16.196

9 cum. (c1. iss-15) My present invention relates to air cleaners and hasfor its object to improve the same in various important particulars,whereby the emciency of the same is increased and the manufacturethereof facilitated, and especially the invention is adapted for use inconnection with internal combustion engines. The improved air cleaner isof very compact formation, has no parts to get out of order or requirefrequent cleaning, and in actual use has been found highly eflicient asused in connection with internal combustion engines designed to run atvery high as well as low speeds.

A commercial -i'orm of the improved air cleaner is illustrated in theaccompanying' drawing, wherein like characters indicate like partsthroughout the several views.

Referring to the drawing:

Fig. 1 is a view partly in elevation but chiefly in vertical sectionshowing the improved air cleaner;

Fig. 2 is a fragmentary plan view of the-air cleaner, some parts beingbroken away;

Fig. 3 is a fragmentary section taken on the line 3 3 of Fig. 2; and

Fig. 4 isa horizontal section taken on the line 4-4 of Fig. 1, .someparts being broken away.

Carburetors used in connection with internal combustion engines, such,for example, as the Ford automobile engine, have air intake tubes towhich theair cleaners are adapted to be attached. For attachment to suchcarburetor intake tubes, the present air-cleaner is provided with anaxial clean air delivery tube 5, which, as shown', is provided at apoint considerably above its lower end, with a Isecured inner flange 8that holds a pliable gasket I adapted to rest upon the intake tube ofthe carburetor, when the latter is telescoped into the lower end of saidtube 5. An annular plate' 8 is secured to the lower portion of the tube5 at a point above the lower end thereof and is provided with anupstanding flange or inverted skirt 9. This bottom plate and flange, aswill presently appear, afford an oil well, and the top of the aircleaner is closed by a hoodforming plate i that is rigidly butdetachably secured, by a nut-equipped stud II, to a crossbar I2, which,in turn, is rigidly secured within and extends diametrically of theupper portion of the tube 5.

Preferably and as shown, the under surface of the plate I0 is providedwith' a silencing lin ing I3 held in place by a woven wire frame I l. Anapproximately cylindrical inner skirt I is secured at I6 to the outerportion of the hood Ill and depends within the outer skirt or ange 9from which it is inwardly spaced, so as to leave. an annular air intakepassage I'I that leads downwardly to the outer portion of the oil wellyI8 formed by the bottom plate 8. An annular baille plate I9 having largeair passages 20, is secured to the upper portion of the air tube 6 andits outer edge is secured to the upper` edge of the inner skirt I5 andto the hoodforming plate I0. 10 As an important feature, the upper edgeof the skirt I5 and the\outer edge of the plate I9 have outturnedmarginal flanges that are interlocked to the plate I0 by a clinch jointformed at I6 by rolling the immediately adjacent portion of the plate I0 around and in air-tight engagement with the said out-turned flanges ofsaid elements I5 and I9. This rolled clinching rib is thus madeapproximately U shaped in radialssection and it is preferably formed ata considerable distance inward from the extreme outer edge of said plateI0, so as to form an cave 2i that overlies the annular air intakechannel I'I, and preferably extends slightly inward of the invertedouter skirt 9. The extreme upper edge of said inverted skirt 9 is bentinwardly at 22 for a purpose which will presently appear. Inasmuch asthe plate, together with the parts attached thereto, is detachable fromthe clean air tube 5, the plate I9 is made detachable from said tube 5;and this 30 as shown, is accomplished by providing said plate I9 at itsinner edge with a downturned cylindrical hub flange I9a that preferablyis of the same diameter as the tube 5 so that it aligns therewith. As afurther feature, a sleeve 23 is telescoped onto the tube 5 and the hubange Isa is telescoped into the extreme upper end of said sleeve 23.\ Asa further important feature, the sleeve 23 is provided near its upperportion below the hub flange I9a with circumferentially spaced perlforations 23a, the important purpose of which will appear in thedescription of the operation. The annular space between the sleeve 23and the inner skirt I5 is filled in with an oil and dustinterceptingscreen y, which may take various forms, but will preferably be of acharacter disclosed and claimed in an application of William H. Schulz,entitled Air cleaner screen and method of producing the same, S. N.725,515, filed May 14, 1934. n

To further hold this annular screen illler in position in -respect tothe removable part of the air cleaner, the lower end of the sleeve 23 isshown as provided with an outwardly projecting flange 23h, and the loweredge of the inner skirt 55 lis Ii is provided with an inwardlyprojecting annular flange Ila. With this structure, when the hood orplate II is detached and removed, the sleeve 28, skirt I and screen ywill be removed therewith and, of course, the said elements will besimultaneously replaced.

In the air cleaner illustrated, the bottom plate l is shown as providedwith an upstanding annular cup-forming flange 24 with circumferentinlly`spaced perforations or oil passages 25; but the structure involving thiscup-forming element. and the well formation are not herein claimed,since the same are the subject matter of an application filed of evendate herewith by Wilfred W. Lowther, entitled Air cleaner.

Operation Under the suction produced by the engineto which the cleaneris applied, vacuum or suction will be produced in the axial air deliverytube Iandthiswillcauseailowofairtotheair cleaner, iirst downward throughthe annular air intake passage l1. thence to the outer portion of theoil well, and from thence over the upper edge of the cup-forming ange 2lup through the oil and dust-intercepting screens and thence to theengine through the delivery tube 5. The air thus delivered against thesurface 'of the oil in the outer portion of the well, will violentlyagitate the oil and will dash the same into a spray or foam that willcarry the oil upward into the screens.

The dust-laden air carried into the screens will be carried upwardtherethrough to an extent depending on the degree of suction, but willnot be carried completely through the same. In fact, the oil under anynormal operation, will not be carried to an altitude above the air portsor perforations 23a of the sleeve 2l. As the air releases the oil, itwill run back through the screens chieily into the cup formed on thebottom plate by the ilange 24. Also, with the cup formation, the oiloverilowing the upper edge of the flange 24 and-running out through theoil ports or passages 2i, will deliver directly into the incomingdust-laden air so that there will be a continuous tendency of the oil toilow outward to meet the incoming air; but as above indicated, this cupfeature action is not herein claimedper se. Of course, the oil that isdelivered to the screen will ilow over`the screen surfaces and willintercept the dust-laden oil and will be, by the latter, carried back tothe oil well, while the clean air will be delivered through the airports 2li, under the hood I0 and through the clean air delivery tube lto the carburetor. When the engine is idle, the oil will -settle backinto the oil well to a normal altitude which will usually beapproximately the lower portions of the screens or the upper edge of theaange 24, when said flange is employed.

'111e tube l is not telescoped around the sleeve 28 in such tight lit asto absolutely-prevent the e of air between the two.

In practice, it is not feasible to make an air- .tight joint between thesleeve 2l and tube 5,

and hence in practice it has been found that'the vacuum produced in thetube 5 and hence through the screens and theair intake passage willcause some flow of oil between said sleeve 23 and tube I with the resultthat some oil will be delivered to the carburetor, which, for obviousreasons, is a lfeature not desired. I haverfoundthaiibyplacingtheairports 23ainthe upper portion of the sleeve 23nearthe top thereof, but below `the joint between the upper edge of thetube I and the hub flange Ila, the vacuum or suction between the saidrelements 23 and 5 will be broken and no oil will be delivered' tothecarburetor by passage between the sleeve 2l and tube i. even when thereis a considerable clearance or looseness of ilt between said elements 23and l.

By the use of the clinched joint Il between the elements i0, i5 and I9,the said three elements are very rmly united and, in practice, I havefound that this may be accomplished by a properly designed rollingmechanism at a very small cost. Moreover, this kind of joint is capableof being produced at a place considerably inward from the extreme outeredge of the hoodforming plate, thereby providing a projecting eave at nonoticeably additional cost.

By reference particularly to Fig. 3, which best sho'ws the joint I8, itwill be noted that the anged edges of the elements l5 and l! would.ilrst be placed together and against the plate I0 and the latter thenrolled and clinched around the marginal ilanges of the said elements Iland l. f

In case of a backre from the engine, there would be a violent rush ofair backward through the air cleaner, which might in some instance, tendto splash some of the oil from the well upward against the inner surfaceof the inverted skirt 9. Hence, said skirt 9 is provided with theinwardly and downwardly curved upper edge flange 22 which would tend tostop and deflect downward any oil thus violently thrown upward againstsaid outer skirt.

A preferred commercial form of the air cleaner has been illustrated, butitv will be understood that various features thereof are capable otvarious modifications within the scope of the invention herein disclosedand claimed.

What I claim is:

1. An air cleaner comprising an axial air delivery tube, anoil-well-iormng bottom plate extended outward from the lower portion ofsaid.

axial tube and provided at its rim with an inverted outer skirt, aninner skirt spaced from said outer skirt and bottom plate to form adownwardly leading annular air intake passage, an air pervious dust andoil-intercepting means in the space between said axial tube and innerskirt, and a hood-forming plate supported above said intercepting meansand the upper end of said axial tube and rigidly secured to the upperedge of said inner skirt and provided with an eaveforming flangeextended above the annular air passage formed between said inner andouter skirts',

2. A n air cleaner comprising an axial air delivery tube, anoil-well-forming bottom plate extended outward from the lower portion ofsaid axial tube and provided at its rim with an inverted outer skirt, aninner skirt spaced from said outer skirt and bottom plate to form adownwardly leading annular air intake passage, an air pervious dust andoil-intercepting means in the space between said axial tube and innerskirt, a hood-forming plate supported above said intercepting means andthe upper end of said axial tube and rigidly secured to the upper edgeof said inner skirt, and provided with an eaveforming flange extendedabove the annular air passage formed between said inner and outerskirts, and av perforated baille plate applied to the upper end of saidaxial tube and having its 15 a,oss,eos

outer edge rigidly secured to said hood and to the upper edge of saidinner skirt.

3. The structure defined in claim 1 in which said hood-forming plate,inward of its outer edge, is formed with an integral annular crimp thatembraces and rigidly engages the upper edge of said inner skirt andsupports the latter.

4. 'I'he structure defined in claim 2 in which said hoodforming plate,inward of its outer edge, is formed with an integral annular crimp thatembraces and rigidly engages the upper edge of said inner skirt and theouter edge of said baille plate and supports said inner skirt.

5. An air cleaner comprising an axial air delivery tube. anoil-well-forming bottom plate extended outward from the lower portionoi' said axial tube" and provided at its rim with an inverted outerskirt, an inner skirt spaced from said outer skirt and bottom plate toform a downwardly -leading annular air intake passage, an air perviousdust and oil-intercepting means in the space between said axial tube andinner skirt, and a hood-forming plate supported above said interceptingmeans and the upper end of said axial tube and rigidly secured to theupper edge of said inner skirt, the upper edge of said outer skirt beinginwardly turned to form a downwardly deflecting oil stop.

6. An air cleaner comprising an axial air delivery tube, anoil-well-i'orming bottom plate extended outward from the lower portionof said axial tube and provided at its rim with an inverted outer skirt,an inner skirt spaced from said outer skirt and bottom plate to form adownwardly leading annular air intake passage, an air pervious dust andoil-intercepting means in the space between said axial tube and innerskirt, a hood-forming plate supported above said f intercepting meansand the upper end of said axial tube and rigidly secured to the upperedge of said inner skirt, and a sleeve telescoped around said axial airdelivery tube and perforated in its upper portion for the purposestated.

'1. An air cleaner comprising an axial air delivery tube, anoil-well-forming bottom plate extended outward from the lower portion oisaid axial tube and provided at its rim with an inverted outer skirt, aninner skirt spaced from said outer skirt and bottom plate to form adownwardly leading annular air intake passage, an air pervious dust andoil-intercepting means in the space between said axial tube and innerskirt, a hood-forming plate supported above said intercepting means andthe upper end of said axial tube and rigidly secured to the upper edgeof said inner skirt, a perforated bame plate applied to the upper end ofsaid axial tube and having its outer edge rigidly secured to said hoodand to the upper edge of said inner skirt, and a sleeve telescopedaround said axial air tube, said intercepting means being securedbetween said sleeve and inner skirt and being removable with saidsleeve, inner skirt and hood plate.

8. An-air cleaner comprising a casing having concentric walls forming anaxial air passage and an outwardly spaced annular air passage, an airpervious dust and oil-intercepting means in the space between said axialair tube and surrounding annular air passage, said axial and annular airpassages being connected i'or the passage of air through saidintercepting means, and a sleeve telescoped around said axial `air tubein loose irictional contact therewith and perforated in its upperportion for the purpose stated.

9. The structure defined in claim 8 in which said sleeve is interposedbetween said axial air tube and the dust and oil intercepting means.

FRANK A. DONALDSON.

